The Blacktip is 57lbs (253N) Thrust, Sierra is 35lbs (156N). Thats 60% more, quite a lot in real terms. Unless you have new batteries in a Sierra you will probably feel an even bigger difference, as old batteries never perform well. The Blacktip with 12Ah batteries also has over 2x the battery capacity.
The Piranha has over 2x the thrust of a Sierra (73lbs (326N) and you can dive all day on 6 low cost battery modules if you have access to power as they change in 45min. But... its a whole different price point from a Blacktip.
Hi Ben, thanks for the reply
Let me say I can't fault our Sierras, they're nearly 10 years old (batteries have been rebuilt) and given few problems other than wear and tear from frequent use. Absolutely had our monies worth
Being pedantic the thrust you quoted for the blacktip was max boost where as standard is 45lbs - still 10 more than the Sierra accepted. But bank for buck upgrade doesn't make sense for us
I've looked at the P3 - only online - its equivalent to the RSin Price, thrust and weight (roughly) which is the category I'd be lookgn at
What made me hesitant was the nylon strap (I'm sure its secure and tested - but it freaks me) but mainly the logistics
If I understand correctly it requires 12 Batteries, and while you quote and ideal 45min charge, I dive in 30C waters, so realistically I'd need two sets to allow the first to cool down, so 24 batteries and 6? chargers per scooter all gets a bit unmanageable (in my head anyway) logistically.
Not sure of the total battery cost (in my region) but it seems comparable with a single large unit - although I appreciate the benefits all to well of being able to just buy a replacement power tool battery rather than rebuild a whole array
So in my case the jury is still out - aided by the fact I'd need to drop over $15k for 2 units plus batteries makes me slower than usual to raid my bank account
But I will be keeping abreast of all the developments