Patrick,
First off, I see you are in San Diego, so you have way many cars/people near you to go see and touch and, maybe, drive. You can use the SOC here to sort by zip code those closet to you. Maybe that will help. If not told already, you should attend the Morro Bay gathering in CA or the Carlisle meet in PA in the spring. This is how you get to see it all, talk to everyone and discover better what will work for you.
I ordered my car turn-key, and worked with JPS (in North Hollywood) to add in the options and features I thought important. In my case that was the high displcement (2332 cc) motor (I like speed and accelerration), big Webers, the beefier so-called Pro-street trans, IRS vs. swing axle, disc brakes, driving lights and stiff sway bars. And of course the colors for paint and interior. Also, I opted for the hybrid tube-frame version that JPS offers, vs. strictly pan-based. I wanted a car that would perform and handle at as high a level as the basic JPS design would allow. As I recall my "research", I was unable to distinguish between the makers by anything other than price and delivery schedule, except that I did come to understand that Intermechanica stands alone and above the rest wrt how far the build can go. Since then, I have learned yet more about the builders and seen/riden/driven a few of the other builders products and personally met and spoken with them. I have had some quality control issues w/ my JPS, and most have been sorted out and the car is very nice, and am very pleased with it on balance. John Steele at JPS has, generally, worked with me in supplying information and parts on a warranty basis to resolve my issues. I am told all of these cars have a period of sorting out when new, and some things go better than others. In my case, I am a bit of a wrench, so taking stuff apart and working on the cars is not a big issue for me. If I had to find a mechanic to do all that was needed (JPS is on CA and I am in MD) the process of sorting would have been very difficult indeed. But that seems pretty much behind me now. All of the builders, in their own ways, stand behind their products and generally bend over backwards to be sure all is right. Some do this even if you bought the car used, vs. new from them directly. I think maybe if doing all over again, I might try the Beck, although the issues of delivery and cost would again have to be examined and factored in and I do not know precisely how those stack up head-to-head today. All of that said, if money and time were no object (BIG if) I would have Henry at IM build me one of his 911 based cars. To me, that would be the ultimate Speedster: all Porsche 911 running gear, vs. VW, full tube frame construction, and Henry's fit and finish. None better. But bring plenty of money (at least 3X the basic Speedster price, I guess), and be aware of how to get it out of Canada and registered where you live.