Thanks everyone for all your lovely comments
Ali cat - I went with full x's in the end, the main reason was because it wasn't always easy to make sure i got all the // crossed on my return leg

I kept finding the odd one i had missed

I did wonder if doing it /// then \\\ was distorting the fabric, or if i was stitching too tight. Anyway I also changed from a hoop to a frame and after i had done that i took out some of my previous projects done with a hoop and noticed some of them were a bit wonky too. I think my problem was caused by pulling the fabric sides when my work was in the hoop to keep it taut! Have since found out that can be a no no lol
Anyhoo you live and learn and i am quite enjoying the 25 ct

need to get a thimble though cos it can get quite tight so one of my fingers is showing the scars lol. Think it's worth it for the coverage though.
Must dash, time for the school run xxx