Spent 20 years building decks in PowerPoint. Roughly three a week, client-branded, brain-numbing. Saw Gamma in my feed for 18 months and ignored it - assumed it was another AI wrapper that'd churn out generic nonsense. Finally caved in February on a throwaway project. Liked it enough to commit to 60 days: every deck from mid-Feb to mid-Apr went through Gamma first, PowerPoint as fallback.

Final tally: 24 decks. 22 stayed in Gamma. Two I rebuilt in PPT from scratch. Here's the sass-free honest bit.

What worked: Time-to-first-draft is genuinely unmatched. Paste in a strategy memo, and within 60 seconds you've got a structured deck with headings, bullet hierarchy, layout that doesn't make you want to cry. Agent Mode (Sept '25) is the real upgrade - tell it 'make slide 7 more visual, less text, frame around client's KPI' and it edits in place. Closer to working with a junior analyst than prompting a tool. Doc-to-deck conversion is the killer feature - I write everything in Notion first, paste it in, boom. Saved me about 62 hours over the two months.

What got it wrong: PPTX export is broken. Not 'slightly off' - broken. Fonts substitute wrong, text boxes resize, colours drift, embedded charts become static images. After deck #3 I stopped promising editable .pptx files. Deliver as PDF and make the client sign off on that. Google Slides export is even worse - don't bother. Free tier is a trap: 400 credits, each deck eats ₄₀, so you get about 10 decks lifetime. No refresh. Go straight to Plus at $8/mo.

The two decks I had to rebuild in PPT: 1) An investor pitch for a pharma client that needed a specific molecular diagram and three dense tables. Gamma flattened the tables into bullet lists, couldn't render the diagram, and brand colours drifted by about 4% on export. 2) A workshop deck for a F500 client who demanded an editable .pptx for version-control. Gamma's export mangled it so badly I couldn't hand it over.

Rule of thumb: Use Gamma when first-draft speed matters and final deliverable is PDF or link. Use PowerPoint when client requires editable .pptx, or you've got dense technical content (tables with 10+ rows, equations, custom diagrams), or you need Pantone-precise brand compliance.

Verdict: Gamma replaces about 80% of my deck work. The other 20% is real and will bite you if you don't plan for it. Would I keep using it? Absolutely - I'm on Pro now at $15/mo. But don't fall for the free tier, and for heaven's sake don't promise anyone a clean PowerPoint export. Happy to answer specifics - kept notes on all 24 decks, including the two I had to rebuild.