Such attitudes do make posting of here less appealing it must be said vectisman. Criticism and cynicism are obviously to be expected, especially about any 'new' or unusual proposals, given how hard it is to be successful in this industry. But it is a shame to see people instantly write things off on here before the full facts and information about it have been made clear.
Planespeaking's comments are to a considerable extent true. However I would think some of the reasons against using a F70 for charter ops also have a benefit as well. They are rather old, although far older aircraft are being used by small and large operators at the moment (Jet2's 733's would be one example). But I would expect this leads to the lease/ownership costs of them to be low, and from what I understand the Fokkers have always fared quite well from a reliability and maintenance side, probably rather better than your average E-Jet if Flybe's are anything to go by (based on personal experiences). The fairly high fuel consumption is very much a negative point especially considering the length of some of the routes.
I would think they are/were unattractive to tour operators due to their size, and the fact that most tour operators aren't looking at a niche market in the same sense as Flylolo (<4hrs block time destinations from an airport with a 1700m runway in a reasonably affluent area with no *direct* competition).
stewyb's comments about the lack of availability and general lack of of F70's in existence (I think Fokker built 47 before they went bust) are also relevant to this. In that regard, I struggle to think of any other aircraft which could fit the role. An F100 or RJ-85 doesn't have the range required, an E170 or 190 could work(?), but I expect the lease/ownership costs of both are a lot higher, especially for the latter owing to their popularity and fact that they are newer designs still in wide use with many major carriers.
Then it's the question of if there are any carriers who have these aircraft available to lease in the peak summer season, to which the answer is presumably very few!
With regard to the operation I hope we see it go ahead, but I do agree some of the destinations seem a little questionable (Pristina seems like a niche market even from London, Murcia's new airport opening at the end of this year is apparently not very well located and serving Tivat as well a Dubrovnik from the get go seems somewhat ambitious to me. It is also good to see the operation has the back of a former TUI boss, hopefully a sign of some credibility.