3's super-congested network! I've had no problems as yet, but I only put the iD SIM in my new Microsoft Lumia 640 paid £129.95 SIM Free. Cry your eyes out Apple £600.
Last time i heard any statement like that someone was trying to sell me something, never the less, you may not see any issues right now, but in (my) testing 3 have come out at the bottom alongside O2... Ha! maybe O2 and 3 are destined to be "The Biggest and Slowest"
Will be an interesting time ahead if/when 3 & O2 merge there user base together, there will be so much fighting over bandwidth between 3's AYCE customers and all the various cheap resellers of 3 and specially O2...
Sorry for my negativity, but just calling it the way I see it!
PS. I suppose your £130 windows phone works effortlessly with other Apple Devices, I assume you can send texts and make calls from your windows computer when it is in range of your wireless network (and soon remote too for customers of Wi-Fi calling), I don't think I need to go on but making statement about an entry-level £130 smartphone vs. a premium device is pointless, i ned not go on