Hi Marty,
Since this forum is for Melabs PicBasic products (PBC and PBP) I'd say that the preference of most people here is one of those. Personally I've never tried any of the others.
Proteus(VSM) is neither an IDE or compiler AFAIK. It's a code simulation package that "runs" your PIC-code on the PC with virtual peripherals such as LCD's etc, some swear by it some hate it - I never tried it.
As far as IDE's goes I use MCS Plus and I like it. It integrates nicely with PBP and with most programmers and comes with bootloader software and firmware for many PICs, built in RS232 terminal, ICD and more. Only thing I'm missing is code folding.
If you're really looking for another compiler, for whatever reason, I'd take a look at Swordfish - only for 18F parts though. There's also the compilers from MikroElektronika, they have a version for the dsPIC's, only one that I know of if your into those.
HTH
/Henrik.
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