Hello Mike D.
I've carried my P7M8 on a daily basis for almost 15 years. It was, like Mr. Bell above, my first handgun. As is common with my approach to new things, I first researched the "best overall" caliber (as though such a thing can be specified with absolute certainty!), then, after deciding that the 9x19, with proper loads & in hollowpoint configuration, offerred the best compromise of effectiveness and ease of use for a new shooter, looked next into the available guns for the caliber. I settled on the P7M8 as likely the best made gun in the 9x19 chambering, both for its intrinsic accuracy, and its safety. (My kids were little then, and the squeeze cocker appealed to me since I was sure my kids couldn't fire it by any means.) Of course, I found that the squeeze cocker permits H&K's "continuous motion principle" to operate in bringing the weapon to bear and firing, without any need for snapping off a safety, yet doing this with a finer trigger pull than any other gun on the market (including Glocks).
Many people write opinionated pieces in the "gunrags", or post on the various gun-related Internet bulletin boards, about how this is an "experts-only" weapon, or how those persons with P7s should use them exclusively, avoiding all other guns. That's as may be. As my first gun, I'm thoroughly familiar with all of the P7's nuances, and remain so, though I've owned (and sometimes carried) dozens of other handguns since. I still have a number of Glocks, SigSauers, and revolvers, and I have absolutely no trouble transitioning from one to the other on the range. I always have a 642 Centennial Smith & Wesson in a pocket nowadays, but am rarely without my P7M8 unless it is so hot that even a lightweight nylon vest is very uncomfortable, which is almost never. You DO have to be able to accomodate the weight of this little gun, and it can't be carried in a pants pocket. Over the years, I've tried a number of approaches, from "deep cover" concealment down the front of the pants (in a homemade rig, before "Thunderwear" existed), to "off-body" methods (specially-adapted briefcases), to belt & shoulder rigs. I've owned AT LEAST two dozen holsters for this gun, including examples from nearly any leather maker you can name, and kydex from BladeTech and Mad Dog. The distillation of all that is this; if you want a secure, tight, properly-positioned belt holster for the P7M8, which takes the weapon's "butt-heavy" property into account (and minimizes it), yet permits the instant acquisition of a proper firing grip, get Ken Null's GSS (Gibralter Speed Scabbard). He makes an excellent offside magazine pouch for the P7, too. (http://www.klnullholsters.com) The Mad Dog kydex completely failed to account for the weapon's weight distribution, and is essentially useless, while the BladeTech holster balanced the weapon very well, but like all kydex belt holsters, left the gun sticking out to the side rather than tucking the weapon in, with the result that the cover garment (vest) was always wearing the paint off the outer part of the rear sight. (The rear of the slide does "stick up in the air" a bit, adding another slight problem to the concealment issue.) Finally, as regards shoulder rigs; a shoulder rig with two-magazine offside carrying capability is an excellent way to carry this gun in a balanced, invisible, and truly comfortable manner. Many "experts" decry the shoulder holster, but it IS comfortable, is better accessed than a belt holster when seated, especially in a car, and can be plenty fast with practise. There is the theoretic concern about violating "Rule #2" (the muzzle is pointing at people and things behind you when the gun is holstered in a horizontal rig, and the muzzle can cross your "off hand" or other people on drawing the weapon), but this is a training issue, not really an equipment issue. Besides, the safety features of the P7 series makes an AD in the holster (assuming a covered trigger guard) impossible, and obedience to Rule #3 takes care of the rest.
I've also had 12 different shoulder rigs over the years (name the makers of your choice), and the absolute no-question best is made by Lou Allessi, and at a bargain price compared to many of the others. (Lou is working on a web site. He used to try to put out a catalogue but could never keep up. Go to
http://www.rfholsters to request a catalogue from his distributor, R.F. Hunting, which will have most of his designs.)
I can't offer any advice about IWB holsters. I despise 'em. They're NEVER as comfortable as belt holsters are, and you can ALWAYS conceal a well-designed belt holster easily with proper attire.
I have the standard sights which came with the gun.
The most accurate (pinpoint!) load in mine is Remington Golden Saber 124gr +P, which has engineered terminal ballistics providing for reliable bullet expansion without fragmentation. This is what I carry. (With two extra mags and one in the chamber , that's 25 rounds.) Cor-Bon has gotten a lot of bad press lately, but their 115gr load seems pretty potent, and has good accuracy and precision in the P7, but not up to the Remington GS standard.
That's my $.04. Good luck!
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"Potius sero quam nunquam."
Very rare occasion that I was willing to gamble $1,000 for a firearm I had only seen in magazines and books! Course, there were a couple of Cooper Arms rifles and that....