I have seen plenty of Red Witches sailing, never seen a Maxi 20 in the flesh. Would not be much in it. I would buy the one you like. Its always good to add up all the boats good bits with boats but always buy with the heart. Forget all that crap about surveys and checks, its all about fun. Some people like MGB's, others like TR4's. If it was me I'd just buy this. http://www.ebay.com.au/itm/390749709886?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

I used to lust after these in the early seventies!

From what I have seen of the performance of both, admittedly many years ago when trailer sailers sailed together in larger numbers , the red witch would have it all over the maxi 20. It may have much to do with the fact that the red witches had a very competitive fleet and raced by better racing sailors . They both sailed in division 5 but the witch always seemed to match some boats in division 4. The maxi never seemed to feature in results much.

The row away factor is always mixed, satisfied to have been out there, but now rowing away from it and have to wait until next time!

Here are the specs for you:
Maxi 20 (shoal draft version)
Loa: 6.09m
Beam: 2.24m
Ballast: 329kg (don't have ballast data for fin keel model)
Sailarea: 19.4sqm

Redwitch: (fixed/fin keel)
Loa:5.94m
Beam:2.33m
Ballast:294kg
SAilarea:16.0sqm

Hope that helps some....