I bought the MEDIUM which fits me pretty well - (I am a 44 year old male, about 5ft 8 and I am about a 36 inch waist if that helps at all)
I was looking for an fancy dress outfit that wouldn't break the bank (lets face it - it'll probably only be worn the once then stuck in the back of the wardrobe) and so this is very good value for money!
GOOD POINTS: you get the outfit which is basically a giant pale blue "baby grow" with a zip at the back, a hat, a yellow belt that goes around the waist and fastens with velcro, with a sash fastened to the back of the belt that you throw over your shoulder and it simply tucks under the belt at the front. (the sash & hat have the Thunderbirds insigna on). You also get a pair of boot covers so you just put these over your normal shoes (although boots are better) so it represents extremely good value for money.
The main outfit is quite good quality - warm enough if you are going to a party where you are staying indoors all night but a bit chilly if you wear this on a pub crawl. The whole outfit looks pretty good and never failed to raise a smile when I wore it!
BAD POINTS. The boot covers are pretty flimsy - basically some very thin foam covered in nylon. I have only worn this once and it was at a reception hall but if I wore this at a disco or pub crawl they will probably be ripped quite easily. The belt ONLY JUST fit - (OK - I weigh 15 stone and have a bit of a pot belly so that doesn't help) but the velcro only just reached!. Bear in mind lads that this is basically an all in one catsuit or leotard so if you are a few stone overweight guys it ain't gonna do you any favours!
Also: GOING TO THE TOILET - NIGHTMARE! as it is a giant "baby grow" there is no zip or flies, so I'm afraid you have to unzip it at the back and slip the top half off your shoulders down past your waist to take a leak (which looks a bit strange when you're standing at the the urinals in the gents) or sit down like a girly girl!!! Also, NO POCKETS! Where do you keeep your cash? there is a little pouch at the end of the sash but this is hardly safe.
Overall I WOULD recommend this product, depending on the venue - a family party, housewarming, birthday party at a hall then go for it!! On a pub crawl on a stag night or at a disco/nightclub - think very carefully! It does look great however and much better than the price tag would have you think.