How many 500W flash units do you know of that are TTL?
Most speedlights are around the 40/50W range I believe and even specialist ones like Quantum QFlash are only ~150W. Bear in mind that with this you have immediate access to the entire catalogue of Profoto's modifiers be it hard or soft and you've got quite a potent product, albeit most likely astronomically expensive.
Price may be prohibitive... though I expect we'll get some clones from China soon enough...
The 'problem' with Profoto is that they are VERY good in terms of performance (I own one alongside my Bowens heads), and they work on the basis of no-compromise in terms of build and ability hence the silly costs (ditto for Broncolor & Briese). The cheaper Chinese ones will always be cutting corners at some point.
I think they've missed an oportunity by not producing some cheaper non-TTL ones, and as a Pocket Wizard owner I'm slightly annoyed they're insisting on going to their own proprietary radio system (my own Profoto has a Pocket Wizard antenna/receiver built-in, works beautifully with PW enabled Sekonic light meters). And I think it would serve them well to make some lights at a bit more of accessible cost to the masses, simply to get them on-board with their system rather than giving in and going for a competitor's make (Elinchrom IMO being the obvious alternative if you can't afford Profoto).
I've been using my 2 Profoto Compact 600 heads for a few years now, along with two Bowens 400w Gemini units, but am now seriously considering replacing the Profotos with a pair of 500W Bowens Gemini simply on grounds of accessories cost, for example a honeycomb grid for the Profoto head is around £250 against about £150-£160 for the same by Bowens. I also want to get a portable battery pack - the Profoto one is completely out of the question, purely on cost.
Both pairs of head units have been equally reliable over the years of use.
Compared to an Elinchrom Ranger Quadra (£1120 @ The Flash Centre) it is more expensive but I wouldn't say the price is too unrealistic. It is 500W vs 400W, and has TTL built-in. You are also argueably buying into a better quality system also (I've used an Elinchrom Ranger Quadra and they are flimsy in comparison).
And as a Profoto owner I will confess I've considered Ranger Quadras for supplimental lights to my 1200W main battery pack but the kicker has always been that it's yet another system to deal with (I already own Bowens as well) so I'm keen to see how these perform (although I'd rather they shaved a few bob off and did non-TTL ones as well).
I'm surprised as well, the $=£ 'equality' winds me up. Maybe a sign of difficult trading time.
If you look at their new universal softbox range introduced in the last year it seems to me that they're aggresively trying to muscle-in on the mid-range market (Elinchrom, Bowens) as they're both decent quality (I own their 5' Octa) and keenly priced.
They've also recently released a range of Cali-Sunbounce like reflectors so they're attacking the competition from multiple angles.