If your sales team is all about high-volume phone outreach and lives on the phone, Close is the clear pick because its built-in autodialer and native calling tools actually speed up that workflow. It's designed for aggressive outbound sales, letting reps burn through call lists without friction, and ties in SMS and email sequences directly.
Streak, on the other hand, just tries to bolt CRM features onto Gmail but ends up slowing everything down and getting messy fast, especially if you're dealing with any real volume. It turns your inbox into a clunky spreadsheet and falls apart as soon as things get busy.
So if you care about actual sales efficiency and your team is dialing all day, Close is the only one that won't drive you crazy. Streak only makes sense if you're married to Gmail and your CRM needs are barely above a basic spreadsheet. For real sales work, skip Streak and go with Close.