I would go for the Type 2 socketed 7.2kW version and a Type 2 to Type 1 cable. You can get the cables a little cheaper if you shop around - go for at least 5m.
Your next car that needs charging is more likely to have a Type 2 connector as Type 1 is becoming less common (Mitsubishi being the largest manufacturer using it, virtually every other car manufacturer that sells in Europe uses Type 2 now). Whilst the Outlander will only charge at up to 3.6kW, your next car may well charge at the higher rate. So for the slight extra cost (about £50) now, you're getting the most out of the grant whilst it still exists for the future. Also you can take the cable with you to use at public charging facilities if you want to, Type 1 ones are very rare but Type 2 are common.
As to which make you go for, that really is personal choice. A lot of people go for Chargemaster because they're cheap and do the job. I went for Pod Point because I think the unit looks better and connects via Wifi so I can see my charging history on my phone. There are others such as Rolec and EO. It's worth getting the list of approved installers from the Government website (it's a big spreadsheet) and filtering it down to the ones that cover your area, then seeing what models they offer.
It is a valid point to weigh up whether you need one at all - if you only every charge overnight and can park the car close to a suitable 13A socket then you may well be fine with the supplied charger. But if you use pre-heat timers to demist the car before you leave in the morning you'll be losing a few miles of range as it can't replenish the battery as fast as the heater uses power. The reduction in charging time from 5-6 hours down to 3 hours doesn't really matter to most people, but it can be handy sometimes. I chose to get one fitted because I don't park near a socket so the convenience of a dedicated charge point made sense - and also because it's quite likely that Government grant may well stop for PHEVs.
2015 Mitsubishi Outlander PHEV GX4H (petrol/electric)
2008 Volkswagen Caravelle (diesel)
(recently departed - 2004 Subaru Outback 3.0Rn (LPG), 1991 Mitsubishi Pajero 2.5 LWB (WVO))