I'm a fan of both.
I love flying, and I love travelling by air.
By and large, the PA28 that costs me £60/hr in a big syndicate satisfies my love of travelling by air. My £4k flexwing equally satisfies my love of flying, at a cost of around £25/hr all-in. I'd be very loath to give up either.
It is as cheap as they tell you, they are very slow (plan on a 40kn cruise and you won't be far out), they will fly from a pocket handkerchief, you will have to look after it yourself, you can put it on a trailer and take it on holiday, and you can always divert any "microlights aren't real aeroplanes" bar talk by asking the noisiest proponent of that view how many hours they flew last week / month / year in their own aeroplane. It will take you a couple of years before you can tackle the sort of weather conditions that you can in the SEP, particularly crosswinds and turbulence.
You won't find anything cheaper or easier to run than a flexwing, nor anything as easy to trailer and take on holiday with you. You will as an SEP licensed pilot take probably twice as much training as you expect, and probably more than some ab-initio students to get checked out - just live with that, it's nothing to be ashamed of.
As to types, I'd personally go for a Raven, Flash 1, Pegasus XL or Pegasus Q, preferably with a Rotax 503 (447 is fine except a little underpowered for pax carrying in the Raven, 462 works okay but is a little more maintenance intensive, Fuji Robin engined aircraft are dirt cheap, but parts are hard to come by). All of those will give you a decent 2-seater for under £4k, possibly under £3k if you get a bargain.
And try and get a deal that includes a trailer, intercom and helmets - otherwise you'll end up spending another £½-1k.
Oh yes, and join the BMAA - that's the source of all wisdom, and their magazine contains the best classified adds.
G