We've been in business for over 35 years, and are very careful about what we sell. We don't want our customers to be disappointed, inconvenienced or injured; and we don't sell junk.
Phones marked "can be customized" or "upgradable" are MADE TO ORDER, and usually ship 10 to 14 business days after you place your order. If you request and pay for fast shipping, that does not lessen the time it takes to make your phones.
Our standard and upgradable phones are nearly identical. There is no difference in quality. There is no reason to pay extra and wait longer for an upgradable phone unless you need an upgrade (special features such as an amplified handset or armored cord).