When I use your gmail PVA accounts probably Google will ask to enter SMS code, because I will use different IP.
I'm the guy who left the first review in April, so I'll share my experience regarding that.
I bought ten and manually logged into each to check em out, and I did this login through TOR using a different identity in the browser each time (so different IP, no saved cookies, etc.). The majority of the accounts let me straight in. A handful asked me to verify by entering the phone number associated with the account, but they were only concerned that I knew what the associated phone number was, not sending a verification SMS. When I purchased the accounts Powerpuff provided both the recovery email (all yahoo accounts) and recovery phone number, so this was easy to provide when requested by Gmail.
I did have once account that let me login fine, but then when tried to access account settings to change the password it wanted me to get an SMS code. But I logged out and waited several minutes and tried again and this time it just wanted to know the phone number. So even if it wants SMS for something it won't necessarily be 100% as long as the account isn't deactivated.
FWIW, I've created alts before without phone verification and found that they got deactivated requiring SMS code when I had several from one IP, whereas I haven't had that issue yet with these just for accessing them and receiving mail.
One issue I did have with these accounts is that they usually get locked and require the SMS code to recover if sending an email through TOR. I think this is expected though, I've seen people mention that happening to their standard personal account as well when using VPNs and TOR. So if you need to reliably send emails from IPs used by many people or IPs that are likely to be abuse-flagged, the Authenticator method is probably a good idea.
Thank you for an honest and informative review!
