If by "proper surround sound" you mean the classic AV Receiver + speaker package, then I'm afraid that what you're seeking in the wireless rear speakers (and to a lesser extent the wireless sub) doesn't exist. There are just too many compromises such as the bandwidth limits of Bluetooth transmission. It's at odds with what a separates AV system is about; which is audio quality and flexibility.
A couple of companies have done (semi-)wireless high fidelity rear speakers, most notably KEF. The rub though was cost. Just the transmitter kit and two speaker system was as much as your entire AV budget. That's before you bought a compatible AV receiver, sub and front speakers.
All-in-one kits are a different proposition, as are soundbars. The priorities here are different. Usually it's about having something compact, and there's more focus on peripheral features such as built-in streaming, apps and maybe app control. Sound quality has been less of a priority. Some of that has changed though as people's expectations of what a soundbar might cost have been challenged by products such as Sonos. Suddenly a soundbar isn't £99 any more.
The Philips kit is decent by soundbar standards, but it can be bettered by more-focussed soundbar products where the emphasis is on fidelity. If you want equal or better sound without the wireless rears then you could spend £300-£400 and be very happy with a simple 2.1/3.1 non-surround sound bar. There are other solutions too.
For those with the right type of room layout, the YSP2700 is one of the latest in a line of reflected soundwave sound bars from Yamaha that stretches back over 15 years. It uses a multi-speaker array to focus beams of sound at reflective surfaces that then create virtual surround sound speakers in a room. They're cleverer than that too. They can run as a 2.1/3.1 system, or even as a "beam-the-sound-to-a-single-point" speaker which is something no-other system does. That means being able to listen late at night at volumes that won't disturb the rest of the house but that give you plenty of sound within a defined bubble. That's pretty cool. The YSP2700 comes with a wireless sub for around the £600-£700 mark. It also makes a good AV hub since the unit has multiple HDMI inputs and supports ARC, 4K UHD and the full gamut of HD audio decoding modes except for ATMOS.
To some extent, sound bars have overtaken the sort of disc-player-based all-in-one-box surround systems that the likes of Comet have been selling for the past 20+ years. The pendulum is swinging away from physical media. Once budgets rise above entry-level, folk are more likely to have a Netfix subscription than rely solely on playing physical media, so there's less call for an integrated disc player, and that gives the advantage to speaker-only solutions such as sound bars.
