I have racks very very similar to the design and build of the RBI racks. Just Canadian!
They are 4 slot CB-70's with 2 rows of 4" flexwatt and they work very well. Very nice looking. Heavy as heck though.
From what I've heard, I'd definitely go RBI over Boaphile any day. Although I've never had a Boaphile rack so I cannot compare quality.
I do not suggest the 3" flexwatt. If you do go the 3" route - stay away from the 10 watt one. I only ever use 4" and 11".
Flexwatt overall is pretty safe and I find from reading around its more likely to melt the plastic around it then to cause a fire - if there happens to be a malfunction. Just make sure you wire it corrently or get someone who knows how to do it correctly, and hook it up to a reliable thermostat and you will be good to go.
I love the look of the PVC racks but honestly they are a bit pricey for what you get. I'd rather get a professionally made melamine rack that essentially does the same thing for loads cheaper. However, PVC racks are a lot more expensive here then in the US.
Hope this helped. :gj: