With that in mind I would definitely reccomend either a 600W HPS or 630W CMH, depending on the budget. CMH has a better spectrum but HPS can be had for less money. Also I’d definitely get the K 200 EC exhaust fan to have some additional headroom for the temperatures at the end of spring as 25°C ambient temp is pretty close to optimum for running LEDs.
Personally, I’m running a Dimlux 600W HPS fixture in my basement after last winter’s harvest was underwhelming and ever since my temperatures are a lot better. In my bedroom I’m getting good results with Sanlight LEDs.
All in all, LEDs are great but the lack of radiant heat can be just as much of a disadvantage as it can be an advantage depending on the many other factors that come into play. There’s no one-size-fits-all solution that’s perfect for every scenario unfortunately. If you plan to run LEDs in a tent with an ambient temperature below ~ 22°C that’s always going to be your bottleneck.
One more possibility to consider is building your own insulated grow box or converting a wardrobe as the fabric tents offer no insulation at all. LEDs might be a feasible option in that case.