If you want impartial, I fly a flexwing and a PA28.
In general, there are more days I could fly the flexwing - although the wind limits are lower, when you run at the world at 45 knots, you can accept much poorer visibility safely than you can at 100kn+. Basically, I'd be happy flying cross-country in borderline VFR in the flexwing, when I'd not even contemplate it at PA28 speeds.
Wind limits, I think the advice you've been given is spot on. I can, and have, operated the flexwing in 12kn X-wind and 25kn total(which would be about my PA28 personal limits), but it's absolutely no fun and my arms ached for days afterwards. Sensible limits at around 15kn total and 8kn X-wind.
To put that in perspective, I've about 100hrs in the PA28 specifically, and about 200hrs in my flexwing (and I should admit, quite a lot of hours in other stuff too).
With regard to piloting skill, I don't think there's a lot between an old aircraft like the XL and a newer machine like the Quik or iXess; newer aircraft (the Quik especially) to be be flown more like the PA28 by which I mean precise speed control, less reliance upon "it feels right" alone and more need for take-off and landing performance calcs.
Other things - safety like any other light aircraft is primarily pilot generated, they are as safe or dangerous as YOU make them. Cross country flying is a rather different beast, great fun but with a lot more re-planning en-route, a lot less ability to have lots of paper in front of you, and very different wind and turbulence limitations.
Finally, join the BMAA - you'll need to sooner or later, so do it sooner and you'll have the benefit of the magazine, HQ assistance, and so-on.
And finally finally, go to the show at Popham at the end of this month.
G