Not a huge diff between them .... I have a 30 yr old 7 1/4" B&D saw .... does the job fine.
This might be of use:
The most important thing is a clamp. Either buy a proper clamp (I bought a 1.2m long one for sheets from Axminster)
Or g-clamp on a piece wood as a guide .... there was a link a while back for a neat home made guide using some sheet plywood
If anybody has that please repost