I can't say enough good things about building these stompbox kits. It totally satisfies that big ole "build monkey" that is always perched on my shoulder when I can't justify building another full up amp (read:"negotiating" the entertainment budget with my lovely wife! ;))
I have built a couple dozen pedals from GGG but haven't yet sampled those from other vendors (e.g., BYOC). But....that will be coming soon.
If you still have the ~$140 in your budget, consider buying a couple of kits to save on shipping costs. I suspect that one of these builds just won't be enough once you get into it!
If that is the case and you use and like delay, consider the PT80 from GGG. It is a great sounding and flexible effect!
I have also built a couple of the BSIAB II with excellent results. There are a lot of way cool mods that can be done to that one.
And...speaking of mods...I have found that liberal use of sockets is key if you intend on doing post build mods. The VERY LAST thing that you will want to do is disassemble a build to tweak a component. I use a very sharp box cutter to liberate the individual metal sockets from a MillMax multi pin assembly and simply solder them onto the board. They work great for transistors, resistors and caps and...even wires!
The only less than stellar effect so far has been the P45 phase shifter. Mind you...it is very clean and full sounding. Just doesn't go as "deep" as I would have liked. Probably should have gone with the P100.
Cheers,
Dave O.