I drove Will's Rosie as my first 70 drive. Did I like it, yes I liked it, would I swap..... Not yet no, until I'm bored of the 50, and that will be the only reason to change.
This is probably the reason for a lot of people, they get bored of the 50 or want something new. Is it better, in some respects yes. The interior without a shadow of doubt is FAR better. Exterior doesn't do it for me and would cost up to 3k to correct.
The exhaust tone, well, that's another 1k on top.
So before I even start to love the 70 I'd need to spend a lot of cash.
Now I have the facelift revup, did I make the right choice, possibly, should I have gone HR, well at the time it was out of my budget, but had I if got one I'd be best pleased with the added power.
Do you swap the HR for a 70, its all about if you like or love the 70. Do you want fresh smelling leather, are you happy with the 70 in standard form?
There's a number of variables only you can answer and a test drive of maybe one or two will help you make that decision.