The bt system is more of a repeater than a proper mesh so you might have to make sure the discs are close enough together to get a good signal and make sure you are connected to the disc that is closest to you. If a dish is getting a poor signal you are going to get the same poor signal just amplified.
Probably will make a difference. You have 4 devices on the 2.4 GHz band and there are only 3 clear channels to use, 1, 6 & 11. So the VM hub will be on one of the channels of one of the discs, so you would probably get interference. Mesh systems like this have an inherent problem in that unless all the ‘discs’ are cabled attached to the VM hub you will play pass-the-parcel with data. Some systems have a 3rd ‘backhaul’ channel (on the 5Ghz band) for talking between stations, but these still suffer from the problem of WiFi being half-duplex.
Tudor There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2