I got a couple of rigid sit-on-tops last year as my daughter wanted one for passing her gcse’s (and of course I had to have one to accompany her).
I got her a 2nd hand Perception Scooter after asking on here, for about £250 which is a good price. It handles well, and is surprisingly quick to paddle, and is very stable.
Conversely, I went for a no-name brand in a bit of a rush. Its got a deep ‘keel’ which means it tracks very well, but you have to push it out further to get in, and often grounds in shallows when the Scooter paddles on. Its also about as hydro-dynamic as a brick, so is hard work paddling any distance.
For transport, I’ve got some bog standard roof bars and taped pipe insulation to them. The kayaks plop on top, on resting at 45 degrees on teh other, and strapped down with some Decathlon kayak straps which are ace, and cheap. I can just about lift each kayak on my own, but easy for 2 people to lift onto teh car.
I store them vertically in my gareage (its got a pitched roof) with a strap around them to stop them moving, up a against teh wall so take up hardly any room there. Kit lives in an Ikea bag! Again Decathlon is good for bouyancy aids. I also got some neoprene gloves and windsurf boots for when it s a bit chillier (definitely fairweather user) but otherwise shorts and t-shirt. Bouyancy aid and paddling a brick keeps me warm!
Got to say they are great fun, we use them in the sea mostly here (Southampton area) – off the beaches and in the natural harbours.
But definitely go for the brands – Perception, Ocean Kayaks, Feelfree – a bit more expensive but plenty of 2nd hand bargains around and they paddle much better.
Edit – you can get an idea of the difference in shape from these 2 pics
[url=https://flic.kr/p/rZzVcw]P4066555[/url] by Allan, on Flickr
[url=https://flic.kr/p/rZAU7f]P4216615[/url] by Allan, on Flickr