Hi again Greeko,
If you want an exact match to your current density it's probably not a good idea to get a stock unit. I had suggested getting one as a place to start, but I think with your level of concern to get the best initial result possible you'd be a lot safer ordering a custom unit.
As far as a lace choice goes I think you'd probably be happy starting out with the SFS/French lace combo (TL 500). It's the best of both worlds, fine swiss lace in the front and more durable (but just as invisible) French lace in the back.
The way to get the closest density match to your own hair possible is to send a few hi res photos taken with a 50 mm lens on a professional grade camera, clearly showing your current natural density taken from various angles in with your order, along with a generous hair sample, your template and a photo of the style you want to achieve as your end result (this one doesn't have to be high res). These few things should provide all of the information the factory needs to make your custom unit as good as it gets.
You should start by making a template that covers the entire top thinning area of your scalp much like the reference photos I posted on page 2 of this thread. On subsequent orders you can make a new template each time to slowly expand the coverage area to suit your needs.
As for matching as the wave/curl of your hair, as I mentioned in my other post, the factory really needs a sample of your natural hair approximately 2" (5-6 cm) in length to determine an exact match. Alternatively you can specify the closest visual match (really just a guess) against a wave/curl chart like this one:
http://qingdaohairwig.com/productshow.asp?ID=562
Following these instructions should give you the best and least detectable change in appearance you want.
I think you're at that stage in your hair loss now where you're still able to pull off hiding quite a bit of density loss with concealer, but that will become more and more difficult to do as you lose more hair over the next few months. Generally speaking, the more hair you have (or look like you do) when you make the transition to a hairpiece, the better and more unnoticeable the results will be. So don't wait too long to make the change.
Once you get your custom unit, you can try it out by taping just the front edge down into position and laying the unit over your own hair to get a rough idea if you think it will work or not before you shave your thinning area for bonding.
The best thing about trying a hairpiece is it's not a permanent procedure. You can always stop wearing it if you determine it's not your thing and get a buzz cut or shave everything clean.
The reality here is you'll never know if this solution will work for you if you don't give it a try. As you've seen, many guys on this forum have made very successful transitions to wearing. Like anything worth doing in life, this kind of change involves a challenge and a learning curve, but the positive change and boost in confidence that comes with it can be worth it... Everything gets better with experience.
Hope you find this helpful.