Two options of hearing aids

I would ask him to let you try them so that you can decide which is best for you. I would not buy online unless you plan to program them yourself.

If Bluetooth is important for you, go with Phonak. The L90 has more sophisticated audio processing. You may try out both the 90 and 70 (with identical settings) and decide if the price difference is worth it.
As Raylock says, you may also consider buying them online and also buy the hardware (around 100 USD) to self-program them, but you need to be very sure you trust the seller (I would not do this from China or on ebay) and check the warranty. Also, if you are not already familiar with Target software this may be a steep learning curve if you are new to this. What I did was buying my Phonaks just over the border in France from a discounter (with initial setup), then did my further adjustments at home, as I was not at all happy with how they were configured. That procedure was not too hard.

As the others said you need to trial both of these aids out in the real world. Not just in her/ his office where it’s very quiet. Go somewhere noisy, restaurant, pub etc. take a small notebook write down what you like and don’t like. We all have trouble hearing in noisy situations, it’s the only way to work out which one suits you best. Wear them to work, talk on the phone, all these everyday situations, it’s the only way for you to work out which one you like best. If the audiologist won’t let you trail them at home do not buy them. Walk away and find one that will let you trial them. What ever you do make sure you return the aids by the due date or you might find you’re buying suds you don’t like.