I own both an Oztent RV1 and a Blackwolf Turbo 270. I'm a regular weekend camper so the following comments should be thought of in that context. I've been using both fairly regularly since I usually go away alone or with my dog.
First up, both of these are fine tents. I realise tent preferences can be specific to your individual circumstances so any comments I make here are only my opinion, and no I do not have any affiliation with either company.
Overall, if I were choosing beteen an Oztent and BW, my verdict would overwhelmingly come down on the side of the BW. Here's why:
1. Set-up/Pack-Up Time
It's true the Oztent is faster. But only marginally. Just like the Oztent, I find the BW only needs a fly in inclement weather. In packing-up time, the Oztent is also faster. But we're talking margins of seconds here. Both are essentially 'speed' tents. And remember, with every BW you get a fly included. No Oztent includes a fly and costs quite a bit extra.
2. Space
Here the BW wins hands down. I am 6'3" and cannot stand up in any Oztent, not even the RV-5, without hitting the roof. All Oztents have a rear sloping side that takes out a lot of living space in the tent. Sometimes my RV-1 feels more like a swag than a tent. In height, width and length, the BW wins easily. The only spatial advantage the Oztent has is in its great awning.
3. Storage
Again the BW wins here. Its shorter, easier to carry and my Turbo Lite 270 feels much lighter than my RV1 (and the Turbo has almost twice as much space). Any RV2 model (2 metres long) or larger generally requires a roof rack. Not so for any BW tents which will fit inside nearly all vehicles.
4. Quality of Materials
The Oztent is superb, no two ways about it. There is nothing I can fault on any of the materials. With the BW, I have the Lite version, not full canvas. Again I cannot fault it and like with my BW I've found it can stand up to any harsh weather conditions.
5. Pricing.
Well, this is what it all comes down to. I paid $399.00 for my Turbo Lite 270 at BCF. That includes a fly and 240cm by 270cm by 200cm high worth of space.
The Oztent RV-1 cost me over $749.00 (full RRP is actually $849.00!!) for 1.5m x 2.15m x 1.45m of space and a slightly faster set-up time and no fly included. The price is more than double the BW.
Overall and genreally speaking, the price differential and extra space means BW is the ideal tent for me and you literally get more tent for your bucks. The only advantage Oztent has is slightly faster pack-up and set-up time. But this is a matter of seconds and I cannot see this being worth hundreds of extra dollars.