I had a Cavalier 1.7 td last year as my winter hack, fitted a boost guage and a bleed valve and had it running 1 bar.

Towing was no issues for it, and was returning a good 45mpg even with my ragging the crap out of it.

Also if you get a cdx spec one, u get air con, leather interior, central locking, 4 elecy windows, abs and cruise control.