I just found this video from Kremerfpv talking about dalprop folder 6" and 7" props. He does a bench test comparing these props to gemfans and dalprop 7" cyclones. I will definitely buy the 7" for my long range. Kind of a game changer for me. Here's a link to the video. He has links of where to purchase in the video description. 

I'm not sure if you also saw the one that Albert Kim posted a few days ago on the 7" versions? If not, it's here...

(28-Jun-2020, 09:52 PM)SnowLeopardFPV Wrote: I'm not sure if you also saw the one that Albert Kim posted a few days ago on the 7" versions? If not, it's here...

Yep just saw that lol. Was just about to watch it. The 7" are pretty hard to find. They are sold out everywhere except for Foxeer.

I didn't see nearly as much jello in this video. Kind of impressive considering that he was flying in windy conditions. I think these props would be perfect for my long range. I don't need speed or thrust as much as I need smooth and efficient. It'll take about a month for me to get these props but I might have to compare these to the cyclones I have on there right now.

I got my 7" fold props today. Gonna fly them in the morning and test them out.

(27-Jun-2020, 06:08 PM)SnowLeopardFPV Wrote: Do 5.1" props fit on the Martian II 220mm frame with the standard arms? I'm currently running the 5" Cyclones and they look really close to the frame already

I have Martian II anniversary edition and 5.1 HQ props   gap between the tip of the prop and standoff is small but I didn't have any problems yet...

AND...........that last post was mid 2020.

DAL FOLDS 5", 6", and much later 3" (not used the 3" size)

When these first came out, a flying buddy and me were getting going with FPV and "only" had analogue quality video, so scraggle was mostly invisible, etc, causing the inevitable clips with greenery and cartwheels along the long grass tangled ground or bare post plough and harrow flinty ground. Usually very much broken prop time.

I saw these appear for sale at 5.1" size and bought straight off.

A sample purchase showed up so many advantages I bought more, and so did buddy. I then found and bought 6" ones as well.

Three years on we are still using them.

They are quiet
They are smooth flying
They have no balance issues
They equate on power (in theory they should be less efficient, but its never been noticable)
They do not seem to reduce battery duration (despite the drag of the non-aero shape hubs)
They are easily assembled and fitted
They can be dismantled for cleaning (more in a min!)

and best of all...........

They reduce the area occupied by a non-flying quad markedly.

With regards cleaning, damp grass does tend to clog the swivel. For a while I carried spares to quick swap, but as we improved this need all but disappeared. A clogged swivel can easily be freed at field or home as follows:-

I use a flat blade screwdriver of the right blade size, slide it into the hub, and twist gently on each hub to free, then pull off. Never broken a hub doing so.

I use a drill of the right size, using it reversed so the smooth shaft enters the hole and then spinning it, even by hand, frees and polishes the "bearing surface" back to right size with a little silicone oil.

A REALLY bad hit will fold one or more blades back and dent the trailing edge impact point near the hub, usually easily smoothed with non-toothed pliers back to shape.

I'm still using blades from 2018/9 when they first appeared!!!

I'm amazed these are not more widely used!!