Cube vs Giant Liv (first road bike)

Both will surely be excellent bikes and seem to have similar specs and gearing.

Fit is more important than anything else so check that the shop has (or can get) the model in the correct size for you.

If that doesn't seal it then choose the one that you like the most. That might sound trite but I think this is a more important factor than some people would have you believe.

Don't forget a good quality lock as sadly bike theft has increased significantly since the start of the lockdown 12 months ago.

My wife has a Liv Avail, and I have another Giant with the Conduct brake system that's on the Avail. The Avail was her first foray into road bikes too, and she found it quite a well behaved and balanced bike that's very easy to live with. On balance I'd go for the Avail, mainly for the better brakes- the cable operated brakes on the Cube just aren't as effective. Apart from that though, I think they're both decent bikes.

Hi Hayley

I don't have experience with Cube or Liv but the latter are made specifically for women so might have more specifics saddles and gerometries. If your Bike shop has both, maybe ask if you can do test rides first. 

As for the more general questions. 
Commute: The bike should be comfortable for long or short rides, however depending what you normally wear on the commute, the road bikes might not have space for mudguards. Also depending on where the bikes are left at work, cheaper bike might be the better option to use.

First Time on Road Bike: You will probably have more of a lean forward position then you are used to, with the seat maybe also being higher and the bars being narrower. You will also have three positions to hold which are 

• Top=hands on the top of the cross bar, usually used when going uphill or cycling more relaxed.
• Hoods=On the top of the brake / gear levers and allows for changes / braking as required. You will probably spend 90% of the time with hands here.
• Drops= the bit that loops down and again allows for gear changes and braking. Only really used for fast sections where you want to be lower to reduce drag. 

On your test cycles, try to use all three postions to see comfort and to confirm you can reach and use the gears and brakes easily. 

Gearing Differences: The FX2 has three gears at the front and 7 at the back. The Liv / Cube has 2 at the front and 10 at the back. If you are cycling currently in the lowest ring at the front, you won't have that option anymore. This will mean you could struggle more up hills (initially). Also you won't have gear numbers anymore but that won't be a hinderance for long but obviously the levers are different so just spend some time testing them to get used to them. 

Sorry for any apparent mansplaining above, I'm sure you will do fine and hopefully it all goes well for you. You will definitely notice a difference on longer rides with it being more comfortable and speedier hopefully but if you have the option, keep both the current trek and whichever new bike you get and use them for specific needs.